Check this out. I found this blog post today and downloaded the version of this software for Mac. It's less than a MB and runs straight away with no setup, no fiddling of any kind. I don't know if it's as simple on Windows but it is available.
 
You get a list of TV and radio channels; click on one and presto! Your watching live Japanese TV. The video quality isn't great but what do expect for free! Now you don't have to wait for torrents, you can watch Japanese TV shows at the same time as everyone in Japan.
 
http://www.japannewbie.com/2009/10/30/japanese-tv-with-keyhole-tv-for-mac/